How Engagement Changes Over Time in a Digital Eating Disorder App: Observational Study

Area of Science:

• Digital mental health
• Eating disorder interventions
• Behavioral science

Background:

• Digital mental health intervention engagement is often a summary variable, underresearched despite its link to symptom change.
• This study examined engagement with a digital eating disorder intervention (Recovery Record) across unique app components and devices (phone, watch).

Purpose of the Study:

• To describe and model user engagement with a digital eating disorder intervention.
• To identify baseline predictors of engagement with the intervention.

Main Methods:

• Participants (N=893) with binge-eating behavior used a digital intervention for 4 weeks.
• Engagement was measured by log type, device type (phone/watch), and overall usage, analyzed weekly.
• Multilevel growth models examined engagement with baseline characteristics and time as predictors.

Main Results:

• Most logs were on phones (96%), and mood logs were most frequent (62%).
• All engagement measures declined over time, but trajectories varied uniquely across participants.
• Female and Hispanic participants showed greater engagement; time was a significant negative predictor.

Conclusions:

• Intervention engagement is more nuanced than typically reported, with unique profiles for components and delivery modes.
• Future research should develop early engagement models using baseline characteristics to predict outcomes and tailor interventions.